South of Country Road 74, One mile east of IL Route 4, Near Lebanon
Site is closed to visitors
Emerald Mound preserves the remains of a Native American earthwork, once part of a complex that included about 140 acres of small mounds and a satellite village to the metropolis of Cahokia. Raised and occupied during the Middle Mississippian period (A.D. 700-1400), the truncated, pyramid-shaped mounds supported civic and ceremonial structures, surrounded by small hamlets or farmsteads.
The Emerald Mound measures about 300 feet at the base, rising to a height of about 20 feet, and is covered with trees and other growth. The site was added in 1971 to the National Register of Historic Places.